For maximum visibility, backing a vehicle requires a driver to:

For maximum visibility, backing a vehicle requires a driver to:
Adjust the mirrors so that the driver can see the intended trailer path.
when driver is moving backward or backing a vehicle, adjusting of mirror is important factor because a driver can see backward from the mirror. 
Always park back in a space. 
There are also other factors a driver should keep in mind:
Turn your head also while backing
back slowly and should ready to stop any moment
if someone is walking behind the vehicle, horn the vehicle etc

Uncle grandma